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On a Red Hat system with RPM 4.0.3-1.03, it seems the options
--nodeps and --force don't prevent the system from checking
dependencies. Therefore, I am not able to update certain packages.
For example,

When I try to resolve a name that is not in DNS but is in my
/etc/hosts file, nslookup refuses to look at /etc/hosts. I want to
look at both /etc/hosts (first) and then dns. My /etc/nsswitch.conf
file has this:

"hosts: files [NOTFOUND=continue] dns"

I have a mixed environment of UNIX platforms, and my other
UNIX boxes (HP-UX and Sun) work with this configuration. Can you
tell me what I am missing with my Linux setup?

I have a Compaq Presario 5000 series PC, on which I've
installed a number of different systems, including Red Hat 7.1,
from which I'm writing this question. When I attempt to install Red
Hat 7.2, I am having a problem getting the installation procedure
to accept keyboard input. I have a USB Compaq Internet PC keyboard.
Has there been a regression in the installation procedure that
causes problems with USB keyboards? If so, is there a
workaround?

I see you are using Red Hat, but for those having the same
trouble using Mandrake, I have seen reports of Mandrake 8.1 having
a file /etc/sysinit/usb that requires the entry
KEYBOARD_AT_START=NO in order for Linux to work and function
correctly with a USB keyboard.

I installed a copy of SuSE, which uses LILO, on my Dell
Dimension L866r, and when I boot, I just get a bunch of 0s and 1s
flowing over my screen. I installed Red Hat 7.2 and it installed
GRUB, which worked. Unfortunately, 7.2 (like all Red Hats from 4.x
onward) can't handle my Nokia Multigraph 447x monitor. I sent an
e-mail to them, but they didn't respond.

Chances are that LILO is having a BIOS geometry problem. Do
you have your BIOS set to some sort of geometry translation?
Usually this is called large disk support, or LBA mode. This will
bring the number of cylinders down to a lower number (hopefully
below 1,024 cylinders) and allow LILO to see the whole disk. If
this isn't possible, make sure that the partition on which your
kernel gets installed (/ or /boot depending on the distribution) is
all contained below 1,024 cylinders. This error also may mean that
LILO interpreted your disk geometry incorrectly. You may have to
tell LILO what your real geometry is, or you may need to give LILO
the “linear” option. Look at section 2.2 at
www.linuxdoc.org/HOWTO/mini/LILO-2.html
for more information.

I have a couple of questions. First, how would you create a
backup user for root with the same privileges as root? Second, is
there a way to allow users to log in only within a specific time
frame? An example of this would be to allow a user to log in
between the hours of 6 A.M. and 6
P.M., but not to allow logins outside of this
window.

Regarding control of login time, there are several ways of
doing it. Using the Pluggable Authentication Modules (PAM) system's
pam_time module is one of them, for instance. The file
/etc/security/time.conf could have the line:

login;*;joe;Al0600-1800

This means the user joe is allowed to use the
service called login, from any terminal (*), all days (Al) only
during 06:00 and 18:00 hours. Be aware that this requires the
entry:

login account required pam_time.so

on the PAM configuration file, which is usually at
/etc/pam.conf or alternatively, the file named login to be within
/etc/pam.d/ and containing:

Currently, I use Red Hat 7.0 on PCs in my computer
programming lab. These computers use DHCP to connect to the
building network and the Internet. Recently I attempted to upgrade
these machines to a stock version of Red Hat 7.2. I have been
unable to get computers to connect via DHCP. I have tried to
configure the card and networking using the various GUI tools but
have had no success.

Looks to me that you are having trouble connecting because of
two possible issues. First, you have not configured the DHCP client
to connect to the network. I just did it on a Red Hat 7.2 machine
by having the minimally configured file
/etc/sysconfig/network-scripts/ifcfg-eth0 for network interface
eth0 as:

DEVICE="eth0"
BOOTPROTO="dhcp"
ONBOOT="yes"

This will provide enough information for the system
to boot up, and when starting networking facilities, to look for an
IP address provided by a DCHP server. Second, you probably set a
firewall or network filter that is not allowing DHCP to work
properly. Did you request a “high” security level when
installing? Just one time, get rid of the ipchains setup that Red
Hat 7.2 sets up by commenting all lines in /etc/sysconfig/ipchains
and then try step one.

The reason the current directory is not in the path is due to
security concerns. If an adversary installed a Trojan ls command in
the /tmp directory and you cd-ed into /tmp and typed
ls, you would run the adversary's program. If
you really don't like having to type ./, place
the current directory at the *end* of your PATH shell variable,
this will make your file system surfing safer.

Many Parallel/USB web cameras are supported by Linux. You
should pick a camera that you are interested in and search the web
to make sure that camera is supported under Linux. Check out
www.openh323.org/h323_clients.html
for video conferencing support.

I guess the best for you would be to visit
www.linux-usb.org
(look for the Working devices list) and
www.freesoft.org/software/NetMeeting.
This HOWTO is about communicating between Microsoft Netmeeting and
Linux. Lastly, video and conferencing in Linux are evolving rapidly
and are subjects in constant improvement. These links may be good
initial references for you to begin with, as they were for some
people who just deployed a large Linux-based videoconferencing
system.